when u are ready to root and flash custom rom, flash a custom recovery like cwm too. NANDROID BACK UP straight away after flashing custom recovery. The cyanogenmod installer is safe to use. I have personally used it and it was smooth. Back up ur efs too. If u dun know wat is efs, go read on it. Good luck rooting and flashing. It is safe unless u dun follow instructions or read carefully.
And backuping the partitiom of the imei code? How i do that and better how i am in danger to lose that?
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